Method of extracting diphenylamine



Patented Sept. 11, 1934 UNITED STATES PATENT GFFICE William T. Ingraham, Dover, N. J.

No Drawing. Application June 7, 1933, Serial No. 674,715

4 Claims.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a method of extracting diphenylamine and its derivatives from smokeless powder.

Smokeless powder that has deteriorated may be ground and reworked into new powder after If the deteriorated powder is to be converted into a product such as nitrocellulose lacquer it is necessary to remove the diphenylamine and its nitro-derivatives as Well as reduce the viscosity of the nitro- It is therefore proposed in the present invention to provide a simple and economical method of removing diphenylamine and its deremoving any free acid present.

cellulose.

rivatives from smokeless powder.

The method consists in grinding deteriorated smokeless powder and treating it with a mixture of a solvent for diphenylamine which is a gelatinizing agent for nitrocellulose and an agent that prevents or retards gelatinization. ample of such a mixture consists of acetone and water, the proportions to be employed depending upon the completeness of extraction desired, the length of time of soaking and the number of Washes.

An ex- A preferred mixture consisting of 70% to 75% acetone and 25% to 30% water, will give almost a complete extraction of the original diphenylamine present in the powder.

Mixtures of equal the mixture.

The ex- Total Fineness of Mixtureace- 55 2 diphenylpowder toneqvater washes hours hours ggglfg Percent In the first two examples given above the washing was conducted at 0., while in the others room temperature was used.

In no case does the solvent cause the smokeless powder to become swollen or adhesive and 0 no difiiculty is experienced in handling the powder during or after extraction.

Another advantage of the process is that it permits the reduction of the viscosity of the nitrocelluxose in the powder without the use of a different solvent. This can be done by treating the powder, subsequent to the removal of the diphenylamine and its derivatives, with acetone containing a quantity of acetic acid.

I claim:

l. The method of treating smokeless powder containing diphenylamine which consists in comminuting the powder, and washing it at room temperature in one or more baths of a mixture composed of acetone 50% to 75% and water 75 50% to 25%.

2. The method of treating smokeless powder containing diphenylamine which consists in comminuting the powder, and washing it in one or more baths of a mixture composed of acetone 50% to 75% and water 50% to 25%.

3. The method of removing diphenylamine from comminuted smokeless powder which consists in submitting the powder to the action of a mixture of acetone to and water 25% to 30%.

i. The method of removing diphenylamine from comminuted smokeless powder which consists in submitting the powder to the action of a mixture of acetone 50 to 75 parts and water 50 to 25 parts.

WILLIAM T. INGRAI-IAM. 

